Alison Klayman’s entertaining, compelling and thought-provoking film, which premiered at the Sundance Film Festival this week, follows the Beijing-based architect, conceptual artist and provocateur as he does battle with Chinese authorities, surviving around-the-clock stakeouts, a beating by police, public denouncement and, eventually, an 81-day prison stint.

What is Ai’s crime? According to Klayman, he’s guilty of publicizing China’s ongoing clampdown.

Ai’s life as a subversive may have began as a child. He saw his father Ai Qing — a famed poet who ran afoul of Communist party leaders — imprisoned and publicly humiliated. By his 30s, Ai had published radical art books — one photo featured his wife defiantly lifting her skirt in Tiananmen Square — and distributed them through China’s black market.

After authorities refused to release the total number of deceased from a 2008 earthquake in Sichuan, Ai filmed documentaries that detailed the damage. Against sometimes violent resistance by police, he began collecting data on the missing.

Ai eventually published a spreadsheet of 5,000 students who had been killed, also displaying it proudly on the wall of his studio. Ai sustained injuries after being beaten by police in Sichuan, and he tweeted every moment (famously sharing a snap of the fluid, in a plastic bag, that surgeons drained from his skull).

Ai covered the exterior of Munich’s Haus der Kunst with thousands of backpacks — metaphors for Sichuan’s missing children—spelling out, in Chinese, “She lived happily in this life for seven years.”

“While he knows the difference between a museum piece and a tweet, he also understands that the artist is the message.”

“Weiwei’s whole life is his creative practice,” Klayman said. “While he knows the difference between a museum piece and a tweet, he also understands that, to update McLuhan, the artist is the message.”

“Without the cat-and-mouse [game] that the Chinese authorities instigate, Ai wouldn’t have nearly the profile he does,” Klayman continued.

Ai has been a part of ArtReview‘s “Power 100” (with perennials like MoMA director Glenn Lowry, gallerist Larry Gagosian and mega-donor Eli Broad), and was also on last year’s Time 100 list. After being arrested in April 2011, Ai’s story caught the attention of Stephen Colbert.

Ai has muted his message since being released from prison in June 2011. Footage from Never Sorry shows him thinner, and looking broken, and he’s under a one-year ban from using social media. Other activists, including the still-imprisoned Nobel Peace Prize winner Liu Xiaobo, have spent years in detention.

Ai refused to do a Skype interview for Sundance, and, gently defiant of the ban, has been tweeting in relatively timid terms: no middle fingers (an Ai signature) to the Chinese government, no “fuck you”s in the captions to his art.

“He’s visited by the cops after every public and media appearance,” Klayman said. “I get the sense he’s trying to wait it out until his bail conditions are released. But that’s only my guess. With so little transparency in China, figuring out what’s next is like reading tea leaves.”